Narrative:The Boeing 707 N7071 was operating on a customer guarantee and acceptance training flight prior to delivery of the plane to Braniff. The plane was being flown by a Braniff captain and a Boeing testpilot as instructor. Other Braniff and Boeing personnel were on board as crew members and observers. A series of Dutch Rolls were performed; one of the rolls was executed beyond the maximum bank restrictions. Control was lost, but the aircraft recovered. During the recovery however, the no. 1, 2 and 4 engines were torn off. An intense fire burned away portions of the jet control near the no. 2 engine attachment area. An emergency descent was carried out and the plane crash-landed along river.

PROBABLE CAUSE: "The structural failure induced during an improper recovery attempt from a Dutch Roll which exceeded the angle-of-bank limits prescribed by the company."

This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path. Distance from Seattle-Boeing Field International Airport, WA to Seattle-Boeing Field International Airport, WA as the crow flies is 0 km (0 miles).